An enterprise with a computer network may wish to provide its employees with access to the enterprise network using remote wireless devices. There are a variety of wireless network carriers serving different geographical areas. Historically, to provide enterprise network access by wireless devices, an enterprise could first determine the required geographic coverage. Next, the enterprise could identify one or more wireless carriers which, together, provide the required geographic coverage. The enterprise could then approach each of the identified carriers and arrange a private communication line between the enterprise network and the wireless carrier (often referred to as a leased line). Thereafter, wireless devices within the geographic scope of the wireless network of one of these wireless carriers could access the enterprise network using the wireless network and the communication line set up between the wireless network and the enterprise network.
An obvious drawback with this approach is that an enterprise that wished to allow wireless communication with the enterprise network over a broad geographic area must make, and maintain, arrangements with many different wireless carriers. Further, a message intended for a wireless device that was disconnected (e.g., off or not in any of the coverage areas) would need to be retained by the enterprise network. This is for the reason that it would not be known with which wireless carrier the wireless device would next register (consequent upon entering, or being turned on within, the coverage area of the wireless carrier). As an enterprise network may not be configured to handle, or to handle efficiently, undeliverable messages until they can be sent, this could prove problematic. Also, any given wireless device will normally be assigned a different (typically IP) address when entering each of the different wireless networks. It may fall on the enterprise network to keep a mapping to the current address of each wireless device.
To address these and other difficulties, a centralised infrastructure was conceived in order to provide centralised management services for wireless communications. Connections were negotiated between the centralised infrastructure and many different wireless carriers in order to provide comprehensive geographic coverage. Further, for an enterprise subscribing to the centralised management services, the centralised infrastructure will receive messages from the enterprise network intended for any wireless device, whether or not the wireless device is currently connected. Where a given wireless device is disconnected, the centralised infrastructure will store the message and forward it to the given wireless device whenever it next registers with one of the included wireless carriers. Additionally, the centralised infrastructure, by holding appropriate mapping tables, allows the enterprise network to communicate with each authorised wireless device no matter what address a given wireless carrier may assign to the wireless device. Yet further, historically, wireless carriers employ web-browser technology. As such, a message to a wireless device registered with a given wireless carrier is stored by the wireless carrier and must be actively retrieved from the wireless carrier by the wireless device. In contrast, using technology described in U.S. Pat. No. 6,701,378 issued Mar. 2, 2004 to Gilhuly et al., the contents of which are incorporated by reference herein, the centralised infrastructure may be configured to push the message onto a wireless device.
With the advent of virtual private networks (VPNs) over the public Internet, the need for a leased line between an enterprise and a wireless carrier has, in many instances, disappeared. This, together with inter-carrier agreements, may make it less difficult to ensure a broad geographic coverage even by concluding a service agreement with only one wireless carrier. Further, newer wireless carriers might employ push technology, might handle disconnects by storing and forwarding messages, and might off-load wireless device addressing problems from the enterprise network. With such high capability wireless carriers and inter-carrier agreements, the aforedescribed centralised infrastructure could become an unwanted added expense.
This invention seeks to ameliorate this potential problem.